Mamuju, Sulawesi Barat Prov., Sulawesi, Indonesia

Dimensions (H x W x D)

8.5 x 14 x 4 cm


231 g

Description & Provenance

This unusual looking specimen is a striking example from a relatively new find in Indonesia. It is a unique outcrop of amethyst marked by its botryoidal habit (which has formed in tiny compact spheres), and its lilac to lavender coloring. The combination of these two details gives it an uncanny likeness to grapes, hence its trade nickname, “grape amethyst.” Notably, some may know these examples by a different name, the find was previously referred to as “grape agate” or “grape chalcedony.” Upon first discovery, the unusual spheres and their very smooth internal structure (when viewed by the naked eye) made many believe the specimens were agate or chalcedony (variations of microcrystalline quartz with a different internal formation). However, closer examination of a thin cross-section revealed that the orbs had a radiating (rather than concentrically banded structure) and a coarser texture, confirming that they were actually special formations of amethyst.

This new and surprising variety of an already beloved mineral has captured the attention of the mineral world and has quickly attained its very own cult following thanks to its strange and beautiful aesthetics. This is a wonderful example with a smooth, plate-like matrix made up of the shimmering amethyst. Atop it are dozens of euhedral, spherical “grapes” that pop against their smooth backdrop. Lustrous and even in tone, this is a great example with all of the hallmark characteristics from the find.

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